I have some questions about filming & editing

Hi. I just bought the GoPro Hero 4 Black, and I'm going to Asia with my girlfriend and we are going to film everything.
I have a few questions.

1. What settings should I use?

I really do like the "cinema look", so right now I am leaning towards 4K 24fps in most shots, and 2.7K 60fps for shots that I will slow down little-bit post, and 1080p 120fps for really slow motion clips. I will do lot of color grading & correcting to make my finale product look cinematic. Will it make a big difference if I choose 24fps or 30fps? What is the biggest differences?

2. Is it a problem to shoot some videos in 60fps or 120fps? I guess not? Since I will slow the footage down to 24fps (the same as the other clips).

3. Also, lets say I will shoot some videos with high speed (but without slow-mo), and I don't want motion blur. Can I use a 60fps footage in my 24fps timeline, without slowing it down, and without losing quality?

4. I want to render everything in 4K post, but what about the "super-slow motion" shots in 1080p? Are they unusable in a 4K timeline? I have a 4K monitor, and high quality is probably the most important thing for me.

I have just started taking video editing more seriously. I hope to get some good answers, so that I know what to do before I start shooting. If there are something else I should know, please let me know!

Useful information:

- I use mostly Adobe Premiere Pro (for editing), and Da Vinci Resolve for color grading
- I use the new iMac 27 Retina 5K